How recent are navy urinalysis?

In february my friend had a birthday party, i didnt know she put marijuana in the cake and i was wondering that if i went to meps it would show up? i was too scared to tell my recruiter. also, do they do blood test at boot camp? i went to meps last year and i ped everything, i was in the dep program and i go back to meps in august. do you think i will p?